Thiyagu gets an average of 50% maximum marks in 5 subjects and those marks are in the ratio of 16 ∶ 8 ∶ 9 ∶ 5 ∶ 2. If the passing mark is 60% of the maximum marks and each subject has the same maximum marks, in how many subjects has he failed in the examination?

Thiyagu gets an average of 50% maximum marks in 5 subjects and those marks are in the ratio of 16 ∶ 8 ∶ 9 ∶ 5 ∶ 2. If the passing mark is 60% of the maximum marks and each subject has the same maximum marks, in how many subjects has he failed in the examination? Correct Answer 4

Given

Passing Percentage in each subject = 60% 

Average marks percentage scored = 50% 

Formula used 

Average = Sum of Data/No. of Data 

Calculation 

Let the marks he scored be 16x, 8x, 9x, 5x, 2x

Let the maximum marks of exam be 100 

Passing marks in each subject = 60% of 100 = 60

So average marks in 5 subject = 50% of 100 = 50 

Now, 50 = (16x + 8x + 9x + 5x + 2x)/5 

⇒ x = 50 × 5/40 = 25/4 

So, Scored in each subject by Thiyagu

1st subject = 16x = 16 × 25/4 = 100 marks 

 2nd subject = 8x = 8 × 25/4 = 50 marks 

3rd  subject = 9x = 9 × 25/4 = 56.25 marks 

4th subject = 5x = 5 × 25/4 = 31.25 marks 

5th subject = 2x = 2 × 25/4 = 12.5 marks 

So, clearly seen in 4 subjects the marks scored is less than 60 

then he failed in 4 subjects

∴ The required answer is 4